Is your feature request related to a problem? Please describe.
The boost-python dependency of boost-mpi is only needed to build the python bindings. As a lot of persons don't need this and building the python3 package takes quite long this sould be a feature.

Proposed solution
keep the python bindings but move them to a feature

Describe alternatives you've considered
Non

Additional context
Add any other context or screenshots about the feature request here.